Recommended File Size for Ntbackup

Can I get some expert options on the recommended backup file (.bkf) size when using ntbackup?  I read one article to suggestion around 250GB.  What are your thoughts?  
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Alan HardistyCo-OwnerCommented:
Recommended based on what?

If your backup needs 300Gb - it needs 300Gb.

Are you planning to restrict the amount of space you can use for a backup and if so, what if your backup exceeds this amount?  If you do that - it will fail.
I'd make them not larger than 4GB. That way you can copy them to a fat32 formated disk without running into the max file-size limit of fat32 (which is around 4GB). Apart from that, it would also fit onto a DVD if necessary. Other reasons for the small size is that if you get a small file-system or disk corruption that would probably make the complete file unusable, while if you have it in smaller chunks only one of those small chunks would be unusable, that would increase the chance of being able to restore at least some of the data.

I think those are also the reasons why other backup utilities split their backups files by default into chunks of around 4GB each.
Alan HardistyCo-OwnerCommented:
You can't tell NTBackup to split the backup files.  If you have a drive formatted with FAT32, it can only write a 4gb file to the drive, then the backup will fail.  If you backup to an NTFS drive, the backup will write as big a file as it needs to complete the backup.

If you want to split the files into more manageable chunks, NTBackup is not the tool for you.
10 Tips to Protect Your Business from Ransomware

Did you know that ransomware is the most widespread, destructive malware in the world today? It accounts for 39% of all security breaches, with ransomware gangsters projected to make $11.5B in profits from online extortion by 2019.

Slav ZabickiSystem EngineerCommented:
I think that you could divide the backup into small separate parts
for example:
1 backup for windows server os only
2nd backup shared file
3rd not shared files

Maybe  the recovery won't be faster but will save your nerves.

by the way - ntbackup is not supported anymore (windows 2008 r2) so better it is to buy 3rd party software. I'm just assuming that someday you may need an upgrade.
DCS12Author Commented:
Sorry for not clarifying.  I am not wanting to split the file.  I have just read articles and posts that the probability of a ntbackup file getting corrupt goes way up when you start reaching 250GB mark.  If that is true then it would help convince the powers that be that a 3rd party solution is what they need.

We will probably will be on this 2003 server for several more years.
Alan HardistyCo-OwnerCommented:
If you are referring to the following article:

Then that was written in 2008 so things may have changed since then.

Can't say I have come across this problem before, but then I don't use NTBackup to backup an entire server :)


Further to alans comment, I think it is a bit premature to say "However, we've recently discovered that NTBackup has a bug: .bkf files over a certain size are basically rendered invalid. The bug crops up when the backup file size grows to somewhere between 150GB and 250GB. " when it is only that one organisation that has experienced it and, as stated, there is no Microsoft KB about it yet. In the case of this article, I would put more weight nehind the idea that the backup media itself was to blame. Any extremely large file stored on non-business grade media (i.e. desktop external hdd / usb key etc) is at risk of corruption due to the unreliability of the media. In contrast, if the same media were to be filled with 3 million very tiny files, you MAY get one or two corrupted files but the other 2999998 files will be fine.

If you are looking for a replacement backup solution, I like and recommend Acronis products. I find them easy to use and fast to backup, restore and generally use. You may be able to save some money by purchasing an older copy of the software as you will be using it on sbs 2003 - if you can find it (you will need true image enterprise server v9 >). Failing that, you could buy a copy from eBay ( or the very latest version (2012) from the Acronis website. Other products can also perform most of, if not all the features that the Acronis prodcuts can do but generally speaking Acronis had a product that could do everything before anyone else that I know of so I stick to them. I find Acronis' ability to 'mount' a backup image as a read-only (or RW but it is slower, obviously) windows explorer drive that you can browse through and restore individual files extremely useful.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
DCS12Author Commented:
Thanks for the comments.  I am already looking into Acronis as it does seem to be used and trusted by a lot of people.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.